Selection of light sources in machine vision systems

Light source is one of the important components in the machine vision system. It directly affects the quality of input data by at least 30% of the application effect. Therefore, the choice of light source for machine vision systems is very important. The purpose of using a light source is to distinguish the measured object from the background as clearly as possible to obtain a high-quality, high-contrast image; to 'freeze' the moving target on the image; to enhance the edge clarity of the target to be measured; to eliminate shadows; to offset noise and increase target brightness; to overcome the interference of ambient light; and to ensure the stability of the image. Machine vision has three major technologies: imaging technology, processing technology, and motion control technology. Imaging technology is inseparable from light sources. The selection and performance of light sources directly affect the success or failure of the system, affecting processing accuracy and speed. Therefore, the light source plays a decisive role in the machine vision system.

Through appropriate light source lighting design, the target information and background information of the image can be optimally separated, which can greatly reduce the difficulty of segmentation and identification of image processing algorithms, while improving the positioning and measurement accuracy of the system, thereby improving the reliability and comprehensive performance of the system. On the contrary, if the light source is improperly designed, it will lead to half the effort in image processing algorithm design and imaging system design. Therefore, the success or failure of the light source design is the primary factor that determines the success or failure of the visual system.